macOS does not normally need as much tuning as Windows. It is recommended that you disable any cloud technology such as iCloud Drive to make sure that you are not backing up the same folder that you are writing audio to. Here is an article from Apple that explains how to disable iCloud Drive and how to get your Desktop and Documents folder back to the local machine that you are working on.
If you are running the macOS operating system on a MacBook Pro, there is an option for GPU switching that you will need to disable. In short, this option allows your computer to switch graphics systems when more than one system is available and battery power becomes limited. Here is an article from Apple that explains this feature and how to disable or enable it.
When upgrading from one version of macOS to another, it is recommended that you reset your NVram. Here is an article from the PreSonus knowledge base that explains this process.
Most of the problems that are seen on macOS revolve around 3rd-party applications. Remove any 3rd-party antivirus software from your system.
One thing that is commonly overlooked when purchasing a new computer is the speed at which the hard drive runs. If you are going with a mechanical drive, you will want to go with a7200 RPM drive connected to aSerial AT (SATA) port. If you are considering a Solid State Drive(SSD), please review the information below.
SSD drives on SATA are recommended as they have much faster write speeds. The SSD drives can be more expensive, but are definitely worth considering.
SSD drives are also available in NVMe storage format, which are much much faster than SSD SATA drives.This is because the NVMe drive has a more direct connection with your motherboard. DATA does not have to travel through the SATA controller.
NVMe storage can be used in some standard PCIe motherboard slots much like a graphics card, but most NVMe drives use the M.2 form factor shown below. You will need to check your motherboard specs to see if NVMe is supported, and which type of NVMe can be used.
USB drives can be hit or miss, as the USB bus itself could be the bottleneck on performance of streaming real time audio. USB ports can use a shared bandwidth(Hub), or have dedicated bandwidth(Direct). You would always want to use a direct USB connection to the computer, not through the front USB port. If your computer has USB 3ports, and you have either a hybrid SSD or 7200 rpm mechanical drive connected over that USB 3 port, it could perform well. However, internal drives are best.
If you are looking at a MacBook Pro, The MacBook is one of a select few laptops to carry USB 3.1. USB 3.1 can technically transfer data between the MacBook and peripherals like USB hard drives at maximum speeds of up to 10Gbps (Gigabits per second), which is 2x faster than the current USB 3.0.
***Stay away from 5400 RPM hard drives. They are too slow for working with audio applications. You may be able to use one at first, when there is not much data written to the drive, but as you fill up the drive, it starts to write to the inner sectors of the drive and this is where they become too slow. You can compensate to some extent by increasing your Device Block Size, but eventually you will reach a point of diminishing returns. You will find the 5400 RPM hard drives in cheaper laptops ($500.00 USD or lower) because they reduce the amount of power consumption to allow for a less powerful battery and system.